drm/i915: Fix KMS regression on Sandybridge/CPT
We should enable FDI normal training on Sandybridge/CPT system
as well.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
[ickle: removed unrelated chunks]
Cc: stable@kernel.org
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 528aa06..5e839c7 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1681,6 +1681,37 @@
udelay(500);
}
+static void intel_fdi_normal_train(struct drm_crtc *crtc)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ int pipe = intel_crtc->pipe;
+ u32 reg, temp;
+
+ /* enable normal train */
+ reg = FDI_TX_CTL(pipe);
+ temp = I915_READ(reg);
+ temp &= ~FDI_LINK_TRAIN_NONE;
+ temp |= FDI_LINK_TRAIN_NONE | FDI_TX_ENHANCE_FRAME_ENABLE;
+ I915_WRITE(reg, temp);
+
+ reg = FDI_RX_CTL(pipe);
+ temp = I915_READ(reg);
+ if (HAS_PCH_CPT(dev)) {
+ temp &= ~FDI_LINK_TRAIN_PATTERN_MASK_CPT;
+ temp |= FDI_LINK_TRAIN_NORMAL_CPT;
+ } else {
+ temp &= ~FDI_LINK_TRAIN_NONE;
+ temp |= FDI_LINK_TRAIN_NONE;
+ }
+ I915_WRITE(reg, temp | FDI_RX_ENHANCE_FRAME_ENABLE);
+
+ /* wait one idle pattern time */
+ POSTING_READ(reg);
+ udelay(1000);
+}
+
/* The FDI link training functions for ILK/Ibexpeak. */
static void ironlake_fdi_link_train(struct drm_crtc *crtc)
{
@@ -1767,27 +1798,6 @@
DRM_DEBUG_KMS("FDI train done\n");
- /* enable normal train */
- reg = FDI_TX_CTL(pipe);
- temp = I915_READ(reg);
- temp &= ~FDI_LINK_TRAIN_NONE;
- temp |= FDI_LINK_TRAIN_NONE | FDI_TX_ENHANCE_FRAME_ENABLE;
- I915_WRITE(reg, temp);
-
- reg = FDI_RX_CTL(pipe);
- temp = I915_READ(reg);
- if (HAS_PCH_CPT(dev)) {
- temp &= ~FDI_LINK_TRAIN_PATTERN_MASK_CPT;
- temp |= FDI_LINK_TRAIN_NORMAL_CPT;
- } else {
- temp &= ~FDI_LINK_TRAIN_NONE;
- temp |= FDI_LINK_TRAIN_NONE;
- }
- I915_WRITE(reg, temp | FDI_RX_ENHANCE_FRAME_ENABLE);
-
- /* wait one idle pattern time */
- POSTING_READ(reg);
- udelay(1000);
}
static const int const snb_b_fdi_train_param [] = {
@@ -2090,6 +2100,8 @@
I915_WRITE(TRANS_VBLANK(pipe), I915_READ(VBLANK(pipe)));
I915_WRITE(TRANS_VSYNC(pipe), I915_READ(VSYNC(pipe)));
+ intel_fdi_normal_train(crtc);
+
/* For PCH DP, enable TRANS_DP_CTL */
if (HAS_PCH_CPT(dev) &&
intel_pipe_has_type(crtc, INTEL_OUTPUT_DISPLAYPORT)) {